Turn your '04 YZ into a 5 speed !!

Hey Fellas,

I too bought a 450F ,an '04, and absolutely loved the motor, handling, everything about it except the 4 spd. tranny. I was at the point I was going to sell it and wait for Yamaha to get off their collective behinds and do the right thing...offer a WR 5 speed in the razor edged YZ package. At the Desert Mountain Enduro this spring, I spoke with Ty Davis about how he dealt with the CR 4spd in his 450. He smiled and told me the '04 WR tranny was a drop in replacement. I asked if he had any durability issues with the WR tranny. His response was if you run a stock motor, there will be no issues with the 5 speed. He said his motor was strong enough to pull the KX 500s on top speed...and he had no issues with the tranny..yet. This was his 3rd race on the tranny and his mechanic would be pulling it apart for a routine inspection.

Armed with this information, I stepped up to the plate and ordered a complete WR tranny, lock, stock and barrel...it is indeed a drop in fit. I test rode it this weekend, and it is the answer to what we have been clamoring for for the past several years. I can slog along and jump around in watermelon sized rocks, drop into a sandwash, and loaf along at 65-70 mph no problem. Why did we have to spend extra cash to do what Yamaha could have done in the first place? Don't care now...mine is "fixed". Cost was a little over 600.00....well spent. Anyone need a used 4 speed?

Very nice! I know a lot of guys have gone with other options like the gearing but I like the fix. I have seen Ty at several of my races and he is one nice guy. Always there to give you advice or talk about his machine or his race that day.

Kudo's to ya brutha! :thumbsup:

Thanks for the information... I've been eyeing these posts for awhile now.

Come taxtime I will probably get me one too.

I'll probably bump this thread for more info then.

:thumbsup:

What do you want for the 4 speed?

Great info!!! I have seen Ty ride, if it holds up to him for 3 races it would hold up to me for a life time.

I will sell you my 4 speed $ 200.00 great shape no wear at all :thumbsup:

yzf450jack

sent a PM

i have an 03 yz450, will that work for me aswell?

It should

Wow thats really cool. I can't remember who it was but somebody put a 426 5-speed in their 450 and said there was some machine work that had to be done for it to fit.

Armed with this information, I stepped up to the plate and ordered a complete WR tranny, lock, stock and barrel...

By that do you mean both shafts, shift drum, forks, shift star, detent etc. in addition to the gears themselves?

Do you have a parts list?

Yes, you need the ENTIRE transmission; 2 shafts, 10 gears, 3 forks and the shift cam. Nothing from one can be used as part of the other. It's about $750, as I understand.

I have a list of the parts needed to make the conversion...the dealer I bought the parts through was not familiar with the swap and sent me some things I didn't need.....about 50$ worth...not a big deal. Putting this gearbox in was the best modification...bar none....that could be done to this bike. (That is assuming it holds up over time)It isn't flashy, no stickers to put on the fender, it just makes the bike work better in a non-motocross environment. I was ready to sell mine before the swap, now, I'm still in love...!

Yes, you need the ENTIRE transmission; 2 shafts, 10 gears, 3 forks and the shift cam. Nothing from one can be used as part of the other. It's about $750, as I understand.

I would think then that you could use YZ 426 ratios also if you preferred a CR 5 speed.

Interesting....

Did you change the entire case and everything, or did you gut yours and change all of the gears?

Also, what was the total $ amount and did you do the work yourself...

I'm Jonesing to do this so bad... :thumbsup:

It was a total drop in swap. I had never had a 450 apart before, but the manual was pretty thorough, (getting the cams timed was a bit of a chore)I did the work myself in one weekend. The only special tools needed was a flywheel puller, and a case splitting tool, which I already had from years of working on my vintage YZ360.(.same tool!)Total cost was 630 smackers, minus about 50$ in misc. parts I really didn't need. It required NO machining, and it works very well. The 426 tranny won't fit without machine work, and I didn't want a CR 5 speed even if it would fit...I ride in all sorts of terrain and a CR tranny, even a 5 speed, is still a pain in the butt.

Interesting, very interesting... this is something I'll definitely have to consider when I get my 450.

Love to find out more info regarding the 03 swap. Anybody?

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